BARRA JOSÉ LUIS
Congresos y reuniones científicas
Título:
Evaluación de las características genotípicas y fenotípicas como predictores de malignidad en citologías orales
Autor/es:
ZARATE AM; BREZZO MM; SECCHI D; LAZOS J; BARRA JL ; BRUNOTTO M
Lugar:
Florianopolis
Reunión:
Congreso; 55ª Reunión Anual de la Región Brasilera de la Sociedad Internacional de Biometría y 15ª Reunión Anual de la Región Argentina de la Sociedad Internacional de Biometría; 2010
Resumen:
Nowadays, complex diseases have begun to be the focus of study to health sciences.
Researchers seek to improve the accuracy of diagnosis of the pathologies since in similar
cellular and symptoms conditions dissimilar phenotypes can be obtained.[1]. In complex
diseases, oral cancer is a one of them that involves environmental factors and several genes
that regulate proliferation and cell death. Epidemiology has described some environmental
risk factors for oral cancer such as the tobacco and alcohol as well as genetic epidemiology
and experimental studies have identified some genes for tumor transformation of cells like
the TP53 gene [2]. The assessment of the value of diagnostic indicators such as symptoms
and genetic testing allows to estimate the sensitivity and specificity of these indicators to
determine the presence / absence of a pathology. But these estimates are only accurate if
based on reliable data, otherwise the final estimate measured with error. Models such as
latent class analysis allows an estimate of the characteristics of indicators even when a
diagnosis is not available [3]. In latent class models both observed and latent variables are
categorical. The categories of the latent variable c = 1, 2 classifying subjects into oral cancer
and disorders oral potentially malignant. The conditional response probability for variable i,
given latent class membership c, is given by , where are free parameters.The probability
that subject j belongs to latent class c is also a free parameter, denoted . We studied
characteristics of age, sex, clinical phenotype (presence of cellular atypia and lesions of oral
soft tissues ), genotype (mutations in exons 5-8 of the TP53 gene), smoking and alcohol
consumption of patients with oral cancer pathology and oral potentially malignant disorders.
The outcome probabilities showed that patients who were aged over 45 years, with smoking
and alcohol consumption and family history of cancer had a high probability of being
classified in class oral cancer.
Researchers seek to improve the accuracy of diagnosis of the pathologies since in similar
cellular and symptoms conditions dissimilar phenotypes can be obtained.[1]. In complex
diseases, oral cancer is a one of them that involves environmental factors and several genes
that regulate proliferation and cell death. Epidemiology has described some environmental
risk factors for oral cancer such as the tobacco and alcohol as well as genetic epidemiology
and experimental studies have identified some genes for tumor transformation of cells like
the TP53 gene [2]. The assessment of the value of diagnostic indicators such as symptoms
and genetic testing allows to estimate the sensitivity and specificity of these indicators to
determine the presence / absence of a pathology. But these estimates are only accurate if
based on reliable data, otherwise the final estimate measured with error. Models such as
latent class analysis allows an estimate of the characteristics of indicators even when a
diagnosis is not available [3]. In latent class models both observed and latent variables are
categorical. The categories of the latent variable c = 1, 2 classifying subjects into oral cancer
and disorders oral potentially malignant. The conditional response probability for variable i,
given latent class membership c, is given by , where are free parameters.The probability
that subject j belongs to latent class c is also a free parameter, denoted . We studied
characteristics of age, sex, clinical phenotype (presence of cellular atypia and lesions of oral
soft tissues ), genotype (mutations in exons 5-8 of the TP53 gene), smoking and alcohol
consumption of patients with oral cancer pathology and oral potentially malignant disorders.
The outcome probabilities showed that patients who were aged over 45 years, with smoking
and alcohol consumption and family history of cancer had a high probability of being
classified in class oral cancer.
